<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <style>
        .box1{
            background-color: red;
            height:100px;
            width: 100px;
            border: 10px;
            padding: 20px;
        }
        .box2{
            background-color: yellow;
            height:100px;
            width: 100px;
            border: 10px;
            padding: 20px;
            box-sizing:border-box;
        }
    </style>
        <div class="box1"></div>
        <div class="box2"></div>
</body>
</html>